/*
 * Copyright (c) 2000, 2013, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 */
/*
 * @author    IBM Corp.
 *
 * Copyright IBM Corp. 1999-2000.  All rights reserved.
 */

package javax.management.modelmbean;

import static com.sun.jmx.defaults.JmxProperties.MODELMBEAN_LOGGER;
import com.sun.jmx.mbeanserver.GetPropertyAction;

import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.ObjectStreamField;
import java.lang.reflect.Method;
import java.security.AccessController;
import java.util.logging.Level;

import javax.management.Descriptor;
import javax.management.DescriptorKey;
import javax.management.DescriptorAccess;
import javax.management.MBeanAttributeInfo;
import javax.management.RuntimeOperationsException;

/**
 * <p>The ModelMBeanAttributeInfo object describes an attribute of the ModelMBean.
 * It is a subclass of MBeanAttributeInfo with the addition of an associated Descriptor
 * and an implementation of the DescriptorAccess interface.</p>
 *
 * <P id="descriptor">
 * The fields in the descriptor are defined, but not limited to, the following.
 * Note that when the Type in this table is Number, a String that is the decimal
 * representation of a Long can also be used.</P>
 *
 * <table border="1" cellpadding="5" summary="ModelMBeanAttributeInfo Fields">
 * <tr><th>Name</th><th>Type</th><th>Meaning</th></tr>
 * <tr><td>name</td><td>String</td>
 *     <td>Attribute name.</td></tr>
 * <tr><td>descriptorType</td><td>String</td>
 *     <td>Must be "attribute".</td></tr>
 * <tr id="value-field"><td>value</td><td>Object</td>
 *     <td>Current (cached) value for attribute.</td></tr>
 * <tr><td>default</td><td>Object</td>
 *     <td>Default value for attribute.</td></tr>
 * <tr><td>displayName</td><td>String</td>
 *     <td>Name of attribute to be used in displays.</td></tr>
 * <tr><td>getMethod</td><td>String</td>
 *     <td>Name of operation descriptor for get method.</td></tr>
 * <tr><td>setMethod</td><td>String</td>
 *     <td>Name of operation descriptor for set method.</td></tr>
 * <tr><td>protocolMap</td><td>Descriptor</td>
 *     <td>See the section "Protocol Map Support" in the JMX specification
 *         document.  Mappings must be appropriate for the attribute and entries
 *         can be updated or augmented at runtime.</td></tr>
 * <tr><td>persistPolicy</td><td>String</td>
 *     <td>One of: OnUpdate|OnTimer|NoMoreOftenThan|OnUnregister|Always|Never.
 *         See the section "MBean Descriptor Fields" in the JMX specification
 *         document.</td></tr>
 * <tr><td>persistPeriod</td><td>Number</td>
 *     <td>Frequency of persist cycle in seconds. Used when persistPolicy is
 *         "OnTimer" or "NoMoreOftenThan".</td></tr>
 * <tr><td>currencyTimeLimit</td><td>Number</td>
 *     <td>How long <a href="#value=field">value</a> is valid: &lt;0 never,
 *         =0 always, &gt;0 seconds.</td></tr>
 * <tr><td>lastUpdatedTimeStamp</td><td>Number</td>
 *     <td>When <a href="#value-field">value</a> was set.</td></tr>
 * <tr><td>visibility</td><td>Number</td>
 *     <td>1-4 where 1: always visible, 4: rarely visible.</td></tr>
 * <tr><td>presentationString</td><td>String</td>
 *     <td>XML formatted string to allow presentation of data.</td></tr>
 * </table>
 *
 * <p>The default descriptor contains the name, descriptorType and displayName
 * fields.  The default value of the name and displayName fields is the name of
 * the attribute.</p>
 *
 * <p><b>Note:</b> because of inconsistencies in previous versions of
 * this specification, it is recommended not to use negative or zero
 * values for <code>currencyTimeLimit</code>.  To indicate that a
 * cached value is never valid, omit the
 * <code>currencyTimeLimit</code> field.  To indicate that it is
 * always valid, use a very large number for this field.</p>
 *
 * <p>The <b>serialVersionUID</b> of this class is <code>6181543027787327345L</code>.
 *
 * @since 1.5
 */

@SuppressWarnings("serial")
// serialVersionUID is not constant
public class ModelMBeanAttributeInfo extends MBeanAttributeInfo implements DescriptorAccess {

    // Serialization compatibility stuff:
    // Two serial forms are supported in this class. The selected form depends
    // on system property "jmx.serial.form":
    //  - "1.0" for JMX 1.0
    //  - any other value for JMX 1.1 and higher
    //
    // Serial version for old serial form
    private static final long oldSerialVersionUID = 7098036920755973145L;
    //
    // Serial version for new serial form
    private static final long newSerialVersionUID = 6181543027787327345L;
    //
    // Serializable fields in old serial form
    private static final ObjectStreamField[] oldSerialPersistentFields = { new ObjectStreamField("attrDescriptor", Descriptor.class), new ObjectStreamField("currClass", String.class) };
    //
    // Serializable fields in new serial form
    private static final ObjectStreamField[] newSerialPersistentFields = { new ObjectStreamField("attrDescriptor", Descriptor.class) };
    //
    // Actual serial version and serial form
    private static final long serialVersionUID;
    /**
     * @serialField attrDescriptor Descriptor The {@link Descriptor}
     * containing the metadata corresponding to this attribute
     */
    private static final ObjectStreamField[] serialPersistentFields;
    private static boolean compat = false;

    static {
        try {
            GetPropertyAction act = new GetPropertyAction("jmx.serial.form");
            String form = AccessController.doPrivileged(act);
            compat = (form != null && form.equals("1.0"));
        } catch (Exception e) {
            // OK: No compat with 1.0
        }
        if (compat) {
            serialPersistentFields = oldSerialPersistentFields;
            serialVersionUID = oldSerialVersionUID;
        } else {
            serialPersistentFields = newSerialPersistentFields;
            serialVersionUID = newSerialVersionUID;
        }
    }
    //
    // END Serialization compatibility stuff

    /**
     * @serial The {@link Descriptor} containing the metadata corresponding to
     * this attribute
     */
    private Descriptor attrDescriptor = validDescriptor(null);

    private final static String currClass = "ModelMBeanAttributeInfo";

    /**
     * Constructs a ModelMBeanAttributeInfo object with a default
     * descriptor. The {@link Descriptor} of the constructed
     * object will include fields contributed by any annotations
     * on the {@code Method} objects that contain the {@link
     * DescriptorKey} meta-annotation.
     *
     * @param name The name of the attribute.
     * @param description A human readable description of the attribute. Optional.
     * @param getter The method used for reading the attribute value.
     *          May be null if the property is write-only.
     * @param setter The method used for writing the attribute value.
     *          May be null if the attribute is read-only.
     * @exception javax.management.IntrospectionException There is a consistency
     * problem in the definition of this attribute.
     *
     */

    public ModelMBeanAttributeInfo(String name, String description, Method getter, Method setter) throws javax.management.IntrospectionException {
        super(name, description, getter, setter);

        if (MODELMBEAN_LOGGER.isLoggable(Level.FINER)) {
            MODELMBEAN_LOGGER.logp(Level.FINER, ModelMBeanAttributeInfo.class.getName(), "ModelMBeanAttributeInfo(" + "String,String,Method,Method)", "Entry", name);
        }

        attrDescriptor = validDescriptor(null);
        // put getter and setter methods in operations list
        // create default descriptor

    }

    /**
     * Constructs a ModelMBeanAttributeInfo object.  The {@link
     * Descriptor} of the constructed object will include fields
     * contributed by any annotations on the {@code Method}
     * objects that contain the {@link DescriptorKey}
     * meta-annotation.
     *
     * @param name The name of the attribute.
     * @param description A human readable description of the attribute. Optional.
     * @param getter The method used for reading the attribute value.
     *          May be null if the property is write-only.
     * @param setter The method used for writing the attribute value.
     *          May be null if the attribute is read-only.
     * @param descriptor An instance of Descriptor containing the
     * appropriate metadata for this instance of the Attribute. If
     * it is null, then a default descriptor will be created.  If
     * the descriptor does not contain the field "displayName" this field is added
     * in the descriptor with its default value.
     * @exception javax.management.IntrospectionException There is a consistency
     * problem in the definition of this attribute.
     * @exception RuntimeOperationsException Wraps an
     * IllegalArgumentException. The descriptor is invalid, or descriptor
     * field "name" is not equal to name parameter, or descriptor field
     * "descriptorType" is not equal to "attribute".
     *
     */

    public ModelMBeanAttributeInfo(String name, String description, Method getter, Method setter, Descriptor descriptor) throws javax.management.IntrospectionException {

        super(name, description, getter, setter);
        // put getter and setter methods in operations list
        if (MODELMBEAN_LOGGER.isLoggable(Level.FINER)) {
            MODELMBEAN_LOGGER.logp(Level.FINER, ModelMBeanAttributeInfo.class.getName(), "ModelMBeanAttributeInfo(" + "String,String,Method,Method,Descriptor)", "Entry", name);
        }
        attrDescriptor = validDescriptor(descriptor);
    }

    /**
     * Constructs a ModelMBeanAttributeInfo object with a default descriptor.
     *
     * @param name The name of the attribute
     * @param type The type or class name of the attribute
     * @param description A human readable description of the attribute.
     * @param isReadable True if the attribute has a getter method, false otherwise.
     * @param isWritable True if the attribute has a setter method, false otherwise.
     * @param isIs True if the attribute has an "is" getter, false otherwise.
     *
     */
    public ModelMBeanAttributeInfo(String name, String type, String description, boolean isReadable, boolean isWritable, boolean isIs) {

        super(name, type, description, isReadable, isWritable, isIs);
        // create default descriptor
        if (MODELMBEAN_LOGGER.isLoggable(Level.FINER)) {
            MODELMBEAN_LOGGER.logp(Level.FINER, ModelMBeanAttributeInfo.class.getName(), "ModelMBeanAttributeInfo(" + "String,String,String,boolean,boolean,boolean)", "Entry", name);
        }
        attrDescriptor = validDescriptor(null);
    }

    /**
     * Constructs a ModelMBeanAttributeInfo object.
     *
     * @param name The name of the attribute
     * @param type The type or class name of the attribute
     * @param description A human readable description of the attribute.
     * @param isReadable True if the attribute has a getter method, false otherwise.
     * @param isWritable True if the attribute has a setter method, false otherwise.
     * @param isIs True if the attribute has an "is" getter, false otherwise.
     * @param descriptor An instance of Descriptor containing the
     * appropriate metadata for this instance of the Attribute. If
     * it is null then a default descriptor will be created.  If
     * the descriptor does not contain the field "displayName" this field
     * is added in the descriptor with its default value.
     * @exception RuntimeOperationsException Wraps an
     * IllegalArgumentException. The descriptor is invalid, or descriptor
     * field "name" is not equal to name parameter, or descriptor field
     * "descriptorType" is not equal to "attribute".
     *
     */
    public ModelMBeanAttributeInfo(String name, String type, String description, boolean isReadable, boolean isWritable, boolean isIs, Descriptor descriptor) {
        super(name, type, description, isReadable, isWritable, isIs);
        if (MODELMBEAN_LOGGER.isLoggable(Level.FINER)) {
            MODELMBEAN_LOGGER.logp(Level.FINER, ModelMBeanAttributeInfo.class.getName(), "ModelMBeanAttributeInfo(String,String,String," + "boolean,boolean,boolean,Descriptor)", "Entry", name);
        }
        attrDescriptor = validDescriptor(descriptor);
    }

    /**
     * Constructs a new ModelMBeanAttributeInfo object from this
     * ModelMBeanAttributeInfo Object.  A default descriptor will
     * be created.
     *
     * @param inInfo the ModelMBeanAttributeInfo to be duplicated
     */

    public ModelMBeanAttributeInfo(ModelMBeanAttributeInfo inInfo) {
        super(inInfo.getName(), inInfo.getType(), inInfo.getDescription(), inInfo.isReadable(), inInfo.isWritable(), inInfo.isIs());
        if (MODELMBEAN_LOGGER.isLoggable(Level.FINER)) {
            MODELMBEAN_LOGGER.logp(Level.FINER, ModelMBeanAttributeInfo.class.getName(), "ModelMBeanAttributeInfo(ModelMBeanAttributeInfo)", "Entry");
        }
        Descriptor newDesc = inInfo.getDescriptor();
        attrDescriptor = validDescriptor(newDesc);
    }

    /**
     * Gets a copy of the associated Descriptor for the
     * ModelMBeanAttributeInfo.
     *
     * @return Descriptor associated with the
     * ModelMBeanAttributeInfo object.
     *
     * @see #setDescriptor
     */

    public Descriptor getDescriptor() {
        if (MODELMBEAN_LOGGER.isLoggable(Level.FINER)) {
            MODELMBEAN_LOGGER.logp(Level.FINER, ModelMBeanAttributeInfo.class.getName(), "getDescriptor()", "Entry");
        }
        if (attrDescriptor == null) {
            attrDescriptor = validDescriptor(null);
        }
        return ((Descriptor) attrDescriptor.clone());
    }

    /**
    * Sets associated Descriptor (full replace) for the
    * ModelMBeanAttributeDescriptor.  If the new Descriptor is
    * null, then the associated Descriptor reverts to a default
    * descriptor.  The Descriptor is validated before it is
    * assigned.  If the new Descriptor is invalid, then a
    * RuntimeOperationsException wrapping an
    * IllegalArgumentException is thrown.
    * @param inDescriptor replaces the Descriptor associated with the
    * ModelMBeanAttributeInfo
    *
    * @exception RuntimeOperationsException Wraps an
    * IllegalArgumentException for an invalid Descriptor
    *
    * @see #getDescriptor
    */
    public void setDescriptor(Descriptor inDescriptor) {
        attrDescriptor = validDescriptor(inDescriptor);
    }

    /**
    * Creates and returns a new ModelMBeanAttributeInfo which is a duplicate of this ModelMBeanAttributeInfo.
    *
    * @exception RuntimeOperationsException for illegal value for
    * field Names or field Values.  If the descriptor construction
    * fails for any reason, this exception will be thrown.
    */

    @Override
    public Object clone() {
        if (MODELMBEAN_LOGGER.isLoggable(Level.FINER)) {
            MODELMBEAN_LOGGER.logp(Level.FINER, ModelMBeanAttributeInfo.class.getName(), "clone()", "Entry");
        }
        return (new ModelMBeanAttributeInfo(this));
    }

    /**
    * Returns a human-readable version of the
    * ModelMBeanAttributeInfo instance.
    */
    @Override
    public String toString() {
        return "ModelMBeanAttributeInfo: " + this.getName() + " ; Description: " + this.getDescription() + " ; Types: " + this.getType() + " ; isReadable: " + this.isReadable() + " ; isWritable: " + this.isWritable() + " ; Descriptor: " + this.getDescriptor();
    }

    /**
     * Clones the passed in Descriptor, sets default values, and checks for validity.
     * If the Descriptor is invalid (for instance by having the wrong "name"),
     * this indicates programming error and a RuntimeOperationsException will be thrown.
     *
     * The following fields will be defaulted if they are not already set:
     * displayName=this.getName(),name=this.getName(),descriptorType = "attribute"
     *
     * @param in Descriptor to be checked, or null which is equivalent to
     * an empty Descriptor.
     * @exception RuntimeOperationsException if Descriptor is invalid
     */
    private Descriptor validDescriptor(final Descriptor in) throws RuntimeOperationsException {

        Descriptor clone;
        boolean defaulted = (in == null);
        if (defaulted) {
            clone = new DescriptorSupport();
            MODELMBEAN_LOGGER.finer("Null Descriptor, creating new.");
        } else {
            clone = (Descriptor) in.clone();
        }

        //Setting defaults.
        if (defaulted && clone.getFieldValue("name") == null) {
            clone.setField("name", this.getName());
            MODELMBEAN_LOGGER.finer("Defaulting Descriptor name to " + this.getName());
        }
        if (defaulted && clone.getFieldValue("descriptorType") == null) {
            clone.setField("descriptorType", "attribute");
            MODELMBEAN_LOGGER.finer("Defaulting descriptorType to \"attribute\"");
        }
        if (clone.getFieldValue("displayName") == null) {
            clone.setField("displayName", this.getName());
            MODELMBEAN_LOGGER.finer("Defaulting Descriptor displayName to " + this.getName());
        }

        //Checking validity
        if (!clone.isValid()) {
            throw new RuntimeOperationsException(new IllegalArgumentException("Invalid Descriptor argument"), "The isValid() method of the Descriptor object itself returned false," + "one or more required fields are invalid. Descriptor:" + clone.toString());
        }
        if (!getName().equalsIgnoreCase((String) clone.getFieldValue("name"))) {
            throw new RuntimeOperationsException(new IllegalArgumentException("Invalid Descriptor argument"), "The Descriptor \"name\" field does not match the object described. " + " Expected: " + this.getName() + " , was: " + clone.getFieldValue("name"));
        }

        if (!"attribute".equalsIgnoreCase((String) clone.getFieldValue("descriptorType"))) {
            throw new RuntimeOperationsException(new IllegalArgumentException("Invalid Descriptor argument"), "The Descriptor \"descriptorType\" field does not match the object described. " + " Expected: \"attribute\" ," + " was: " + clone.getFieldValue("descriptorType"));
        }

        return clone;
    }

    /**
     * Deserializes a {@link ModelMBeanAttributeInfo} from an {@link ObjectInputStream}.
     */
    private void readObject(ObjectInputStream in) throws IOException, ClassNotFoundException {
        // New serial form ignores extra field "currClass"
        in.defaultReadObject();
    }

    /**
     * Serializes a {@link ModelMBeanAttributeInfo} to an {@link ObjectOutputStream}.
     */
    private void writeObject(ObjectOutputStream out) throws IOException {
        if (compat) {
            // Serializes this instance in the old serial form
            //
            ObjectOutputStream.PutField fields = out.putFields();
            fields.put("attrDescriptor", attrDescriptor);
            fields.put("currClass", currClass);
            out.writeFields();
        } else {
            // Serializes this instance in the new serial form
            //
            out.defaultWriteObject();
        }
    }

}
